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Department: Material science and engineering

Discipline: Finite element method

By: Anelia Ivanova To: Prof. V. Iliev

Subject : Hydrodynamics Simulation

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Table of contents

Review of the problem

Creation of geometry

Meshing

Defining the material property

Boundary conditions

Results

Answers on some questions

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Incompressible Newtonian fluid flows through the valve is controlled by distance h of the flap A. The fluid velocity at the inlet is 2 m/s.

Submit:

The stream lines when h = 15 mm.

The pressure field when h = 30 mm.

The velocity field when h = 45 mm.

The dependence between the mean velocity V2, the values of the h and the viscosity.

Assignment:

Review of the problem

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Creation of geometry

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Creation of geometry

h = 15 mm h = 30 mm

h = 45 mm

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Meshing

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Meshing

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Meshing

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Defining the material properties

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Defining the material properties

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Defining the material properties

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Defining the material properties

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Boundary Conditions

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Boundary Conditions

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Boundary Conditions

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Solution

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ResultsThe stream lines when h =15 mm

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ResultsThe pressure field when h = 30 mm

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ResultsThe velocity field when h = 45 mm

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2,65

2,7

2,75

2,8

2,85

10 15 20 25 30 35 40 45 50

Distance h of the flap [mm]

Mean v

elo

cit

y [m

/s]

Dependence between the mean velocities at the outlet Dependence between the mean velocities at the outlet and the distance and the distance hh of the flap of the flap

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Answers of the questions1.1. What does the term “incompressible fluid” mean and where What does the term “incompressible fluid” mean and where

it is treated in the solution?it is treated in the solution?

Incompressible fluidIncompressible fluid is a fluid which is not reduced in volume by an increase in pressure.

2. What does the term “Newtonian fluid” mean and where 2. What does the term “Newtonian fluid” mean and where it is treated in the it is treated in the solution??

A Newtonian fluid is a fluid whose stress at each point is linearly proportional to its strain rate at that point. All gases are Newtonianand most common liquids such as water, hydrocarbons, and oils.  A simple equation to describe Newtonian fluid behaviour is

where  is the shear stress exerted by the fluid , [Pa] μ is the fluid viscosity , [Pa.s] (du/dy) is the velocity gradient perpendicular to the direction of shear,[s-1]

du

dy

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Answers of the questions3. What element type was used?3. What element type was used?

The type of the elements which was used is tetrahedra.

4. What element options were used?4. What element options were used?

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5. How many nodes and elements were created?5. How many nodes and elements were created?

Answers of the questions

h = 15 mm h = 30 mm h = 45 mm

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6. What is the % error for your solution?6. What is the % error for your solution?

Answers of the questions

h = 15mm

h = 30mm

h = 45mm

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